When someone is put on dialysis, ideally they must see a dietician. A dietician who is experienced in seeing dialysis patients would assess your food habits, your blood investigation results and then customize your diet according to your needs. In India, however, many nephrologists hand out a one-size-fits-all diet plan and do not insist on a diet consult. This could be because the patient would see this as a waste of money.
The trouble with a standard renal diet plan is that a lot of unnecessary restrictions are imposed. This results in the patient getting extremely frustrated and often, going into malnutrition which is a bigger problem than eating the wrong food.
If someone is on regular, thrice weekly dialysis, they do not really need to restrict their diet so much. You need to know the basics of Potassium, Phosphorus, Sodium and fluid and you can actually bring in a lot of variety into your diet. Food can really be much better!
In fact, there is a very small list of foods that must totally be avoided. Everything else can be had in moderation. I once overheard a tech talking to someone who had been on dialysis for the last 3-4 years. The patient said he had not tasted a mango for the past 3-4 years! Yes, mangoes are very high potassium fruits but I am sure, by checking with your nephrologist or dietician, a small slice once in a way in the first half an hour of dialysis, especially if you're getting regular, thrice weekly dialysis, cannot be that bad!
The key is moderation! You obviously cannot binge on fruits but a little fruit once in a way cannot kill you. There are people who get so completely swayed by the not completely thought through advice on diet that they take things to other extremes. And an over-enthusiastic spouse or offspring does not help!
Once someone is on dialysis for a while, say a couple of years, they figure out, by and large, what works and what does not work. They have tried different stuff, stretched the limit, little by little and know their bodies well enough to actually disregard the diet chart given to them and do their own thing.
The way we humans think, it is better to have a small quantity of something in safe circumstances than to crave it so badly that it leads us to depression!